Such an X-ray imaging apparatus for rounds is configured to electrically move among hospital rooms by disposing an X-ray tube and a collimator at the fore end of an arm movable up and down along a supporting post disposed on a cart and driving a motor provided in the cart (see Patent Literature 1). In such an X-ray imaging apparatus for rounds, when moving among hospital rooms, the arm is moved down along the supporting post, and fixed by a fixing mechanism at a fixing position where the arm comes into abut with a fixing part called an arm catch. On the other hand, when taking X-ray images, an operator operates a fixation release button to thereby release the fixation of the arm, and moves up the arm together with the X-ray tube and the collimator to arrange the X-ray tube and the like at positions suitable for X-ray imaging.